PVC木塑复合材料热解动力学

将木粉按一定比例添加到PVC中得到复合材料,通过热重分析研究复合材料在空气、N2气氛下不同升温速率时的热解行为。通过Doyle和Tang method法计算了木塑材料的降解活化能。利用活化能分布函数,分析了复合材料在热解、燃烧过程中不同阶段的反应活性变化规律。研究表明,热解过程可分为3个阶段,230～360℃为第一失重阶段,360～430℃为稳定阶段,430～580℃为第二失重阶段。升温速率及反应气氛对热解过程有显著影响。由分布活化能模型计算表明,其热解动力学为一级反应,两个失重阶段的活化能分别为220kJ·mol-1和139kJ·mol-1,反应活性随失重率的增加而减少。

Pyrolysis kinetics of wood-plastic composite materials about PVC

Obtain composite materials which was added a certain percentage of wood flour to PVC.Thermogravimetric analysis （TG）was used to study the pyrolysis characteristics of composite materials, at different heating rates,in the stream of air or N2 .Comulate the composite materials＇ distribution activation energy through Doyle and Tang method. The results of the pyrolysic experiment indicate that the degradation process can be divided into three stages,the first weight loss stage of 230～360℃,thermally stable stage of 360-430℃ and the second weight loss stage of 430-580℃ The thermal degradation behaviors of composite materials resin are affected greatly by heating rate and atmosphere. Activation energies of them were obtained by using distribution activation energy mode, by which the process of composite materials pyrolysis can be described by using three first-order reaction correctly .The distribution function of energy reveals the rule that the reaction activity of mass changes in differrent stages of pyrolysis,which helps to investigate the mech -anisms of pyrolysis,gasification and combustion,the reactivity reduced with the increase in weight loss.